#!/bin/bash
#
# Copyright 2017 Istio Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
################################################################################
#
ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"

# Install required clang version to a folder and cache it.
CLANG_VERSION_REQUIRED="3.8.0"
CLANG_DIRECTORY="${HOME}/clang"
CLANG_FORMAT="${CLANG_DIRECTORY}/bin/clang-format"

CLANG_VERSION="$(${CLANG_FORMAT} -version | cut -d ' ' -f 3)"
if [[ "${CLANG_VERSION}" != "${CLANG_VERSION_REQUIRED}" ]]; then
  echo "Installing required clang-format ${CLANG_VERSION_REQUIRED} to ${CLANG_DIRECTORY}"
  mkdir -p ${CLANG_DIRECTORY}
  curl --silent --show-error --retry 10 \
    "http://releases.llvm.org/${CLANG_VERSION_REQUIRED}/clang+llvm-${CLANG_VERSION_REQUIRED}-x86_64-linux-gnu-ubuntu-14.04.tar.xz" \
    | tar Jx -C "${CLANG_DIRECTORY}" --strip=1 \
  || { echo "Could not install required clang-format. Skip formating." ; exit 0 ; }
fi

echo "Checking file format ..."

pushd ${ROOT} > /dev/null

SOURCE_FILES=($(git ls-tree -r HEAD --name-only | grep -E '\.(h|c|cc|proto)$'))
"${CLANG_FORMAT}" -style=Google -i "${SOURCE_FILES[@]}" \
  || { echo "Could not run clang-format." ; exit 1 ; }

CHANGED_FILES=($(git diff HEAD --name-only | grep -E '\.(h|c|cc|proto)$'))

if [[ "${#CHANGED_FILES}" -ne 0 ]]; then
  echo "Files not formatted: ${CHANGED_FILES[@]}"
  exit 1
fi
echo "All files are properly formatted."

popd
